The New York Convention for Recognition and Enforcement of Foreign Arbitration Awards of 1958 - ratified by Republic of Bulgaria in 1961, published in State Gazette No. 2 of 1965.
The European Convention for International Commercial Arbitration - ratified by republic of Bulgaria in 1964, published in State Gazette No. 57 of 1964.
A complete list of all the states ratified both the conventions is available at the Secretariat of the Arbitration Court at the BCCI.